[PATCH v4 3/6] iommu: Add return value rules to attach_dev op and APIs

[Tian, Kevin]

> From: Nicolin Chen <nicolinc at nvidia.com>
> Sent: Wednesday, September 21, 2022 4:23 PM
> 
> 
> +/**
> + * iommu_attach_device - Attach a device to an IOMMU domain
> + * @domain: IOMMU domain to attach
> + * @dev: Device that will be attached
> + *
> + * Returns 0 on success and error code on failure
> + *
> + * Note that EINVAL may be returned as a soft failure if the domain and
> device
> + * are incompatible due to some previous configuration of the domain, in
> which
> + * case attaching the same device to a different domain may succeed.

Revise a bit:

 * Note that EINVAL can be treated as a soft failure, indicating
 * that certain configuration of the domain is incompatible with
 * the device. In this case attaching a different domain to the
 * device may succeed.

Apart from that:

Reviewed-by: Kevin Tian <kevin.tian at intel.com>